• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1129-1134
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• 1999

The rapid development of the sheep genetic linkage map over the last five years has given us the ability to follow the inheritance of chromosomal regions. Initially this powerful resource was used to find markers linked to monogenic traits but there is now increasing interest in using the genetic linkage map to define the complex of genes that control multigenic production traits. Of particular interest are those production traits that are difficult to measure and select for using classical quantitative genetic approaches. These include resistance to disease where a disease challenge (necessary for selection) poses too much risk to valuable stud animals and meat and carcass qualities which can be measured only after the animal has been slaughtered. The goal for the new millennium will be to fully characterise the genetic basis of multigenic production traits. The genetic linkage map is a vital tool required to achieve this.

• Asian-Australasian Journal of Animal Sciences
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• 제6권2호
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• pp.225-234
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• 1993

A total of 333 carcasses were evaluated for hindquarter traits: round weight, percent round, loin weight, percent loin, flank weight and percent flank. Other characteristics included: total retail, lean trim, fat trim, round steaks, rump, sirloin tip, loin steaks, percent loin steaks and flank steaks. Mating types included straightbred Angus and Santa Gertrudis, the reciprocal crosses of these two breeds and Gelbvieh ${\times}$ Angus. Breed of sire and breed of dam were significant for most of the traits evaluated. Calf year and slaughter group were also significant. This could be the result of environmental variations. Effect of sire within sire breed was non-significant for all the traits considered. Heterosis due to interaction between sire breed ${\times}$ dam breed was found significant for percent total retail cuts based on hindquarter weight. Generally, Santa Gertrudis purebreds were more desirable in cut out characteristics than all other breeding types followed by crossbreds of Angus ${\times}$ Santa Gertrudis.

• 대한수의학회지
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• 제53권1호
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• pp.7-10
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• 2013

A study was conducted to determine the interdependence among the conformation traits of 28 "Pallaresa" cows using principal component analysis. Originally 21 body linear measurements were obtained, from which eight traits are subsequently eliminated. From the principal components analysis, with raw varimax rotation of the transformation matrix, two principal components were extracted, which accounted for 65.8% of the total variance. The first principal component alone explained 51.6% of the variation, and tended to describe general size, while the second principal component had its loadings for back-sternal diameter. The two extracted principal components, which are traits related to dorsal heights and back-sternal diameter, could be considered in selection programs.

• Asian-Australasian Journal of Animal Sciences
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• 제21권7호
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• pp.941-946
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• 2008

Single-minded 1 gene (SIM1) is a homolog of Drosophila SIM1 gene which plays a key role in the midline cell lineage of the central nervous system and is implicated in the regulation of feeding behavior and obesity in the human and mouse. In this study, porcine SIM1 gene was firstly mapped to chromosome 1p13 using radiation hybrid (RH) mapping and two polymorphisms were detected at position 607 (A/G) in SIM1 intron7 and position 780 (C/T) in SIM1 exon8. The last substitution was genotyped in a 364 F2 animal-population and an association analysis of these genotypes was performed with growth, carcass and meat quality traits by the statistical animal model. The results showed the significant influence of the SIM1 genotype on growth (p<0.05): live weight at birth, later period of growth and average daily gain; and effects on carcass composition (p<0.05): weight of head and buck kneed foreleg, backfat depth, loin eye area, carcass leaf fat and ham fat weights; and traits related to intramuscular fat content (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• 제12권7호
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• pp.1142-1151
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• 1999

Today, laboratory animal production has decreased world-wide to half the number estimated in 1970 of more than 100 Mio. This is due to the cell-biological assays which replaced animal experimentation as a first allround method to solve biomedical problems. Animal experimentation remains the most significant experimental method for the study of higher organized physiological systems and their multifactorial connections. This requires maximal uniformity of all quantitative traits among the animals used for such studies (mainly mice and rats) and stability of these traits for reproducing such studies at any time world-wide. The success of the developed methods for the standardization of laboratory animals was analyzed and were found only partly be acceptable. Getting a higher degree of uniformity among standardized inbred animals is blocked by "intangible variance". This is caused by influences of ooplasm, shown by experimental twin and clone studies. Manipulation of this component of variance is essential in the future. - Genetic drifts impair the necessary stability of biological traits. There are a few disadvantages associated with the cryopreservation of embryos and other methods are required. - Dogs and cats were replaced by pigs as laboratory animals. A new line of animal production will evolve over the next 25 years with similarities to the present laboratory animal production, because in future pigs were used as donors for xenotransplants for men.

• Asian-Australasian Journal of Animal Sciences
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• 제30권8호
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• pp.1081-1085
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• 2017

Objective: Previously, we reported quantitative trait loci (QTLs) affecting backfat thickness (BFT) traits on pig chromosome 5 (SW1482-SW963) in an F2 intercross population between Landrace and Korean native pigs. The aim of this study was to evaluate glutamate receptor-interacting protein 1 (GRIP1) as a positional candidate gene underlying the QTL affecting BFT traits. Methods: Genotype and phenotype analyses were performed using the 1,105 $F_2$ progeny. A mixed-effect linear model was used to access association between these single nucleotide polymorphism (SNP) markers and the BFT traits in the $F_2$ intercross population. Results: Highly significant associations of two informative SNPs (c.2442 T>C, c.3316 C>G [R1106G]) in GRIP1 with BFT traits were detected. In addition, the two SNPs were used to construct haplotypes that were also highly associated with the BFT traits. Conclusion: The SNPs and haplotypes of the GRIP1 gene determined in this study can contribute to understand the genetic structure of BFT traits in pigs.

• 한국수산과학회지
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• 제42권6호
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• pp.591-599
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• 2009

Genetic parameters for growth-related traits were estimated in 9-month old of two Korean abalone subspecies, Haliotis discus hannai and H. discus discus, using multiple traits of animal model. The data were collected from the records of 3,504 individuals produced from 16 sires and 17 dams in H. discus hannai and 821 individuals produced from 3 sires and 4 dams in H. discus discus, which was evaluated at the Bukjeju branch, NFRDI, from May 20, 2004 to February 14, 2005. The heritability estimates obtained from restricted maximum likelihood (REML) method range from 0.29 to 0.31 for three growth traits (shell length, shell width and body weight) in H. discus hannai and from 0.22 to 0.28 in H. discus discus, respectively. The heritabilities for shell shape and condition factor were lower than others of growth traits such as ranging from 0.03 to 0.24 in H. discus hannai and from 0.06 to 0.11 in H. discus discus, respectively. Genetic and phenotypic correlations were >0.91 between shell parameters and weight in two abalone subspecies, respectively, indicating that breeding for weight gains could be successfully achieved by selecting for shell length.

• Asian-Australasian Journal of Animal Sciences
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• 제31권1호
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• pp.19-25
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• 2018

Objective: In practical breeding, selection is often performed by ignoring the accuracy of evaluations and applying economic weights directly to the selection index coefficients of genetically standardized traits. The denominator of the standardized component trait of estimated genetic evaluations in practical selection varies with its reliability. Whereas theoretical methods for calculating the selection index coefficients of genetically standardized traits account for this variation, practical selection ignores reliability and assumes that it is equal to unity for each trait. The purpose of this study was to clarify the effects of ignoring the accuracy of the standardized component trait in selection criteria on selection responses and economic weights in retrospect. Methods: Theoretical methods were presented accounting for reliability of estimated genetic evaluations for the selection index composed of genetically standardized traits. Results: Selection responses and economic weights in retrospect resulting from practical selection were greater than those resulting from theoretical selection accounting for reliability when the accuracy of the estimated breeding value (EBV) or genomically enhanced breeding value (GEBV) was lower than those of the other traits in the index, but the opposite occurred when the accuracy of the EBV or GEBV was greater than those of the other traits. This trend was more conspicuous for traits with low economic weights than for those with high weights. Conclusion: Failure of the practical index to account for reliability yielded economic weights in retrospect that differed from those obtained with the theoretical index. Our results indicated that practical indices that ignore reliability delay genetic improvement. Therefore, selection practices need to account for reliability, especially when the reliabilities of the traits included in the index vary widely.

• Animal Bioscience
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• 제36권1호
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• pp.19-28
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• 2023

Objective: The objective of this study was to perform genome (genome wide association studies [GWAS]) and chromosome (CWAS) wide association analyses to identify single nucleotide polymorphisms (SNPs) associated with growth traits in registered Simmental and Simbrah cattle. Methods: The phenotypes were deregressed BLUP EBVs for birth weight, weaning weight direct, weaning weight maternal, and yearling weight. The genotyping was performed with the GGP Bovine 150k chip. After the quality control analysis, 105,129 autosomal SNP from 967 animals (473 Simmental and 494 Simbrah) were used to carry out genotype association tests. The two association analyses were performed per breed and using combined information of the two breeds. The SNP associated with growth traits were mapped to their corresponding genes at 100 kb on either side. Results: A difference in magnitude of posterior probabilities was found across breeds between genome and chromosome wide association analyses. A total of 110, 143, and 302 SNP were associated with GWAS and CWAS for growth traits in the Simmental-, Simbrah- and joint -data analyses, respectively. It stands out from the enrichment analysis of the pathways for RNA polymerase (POLR2G, POLR3E) and GABAergic synapse (GABRR1, GABRR3) for Simmental cattle and p53 signaling pathway (BID, SERPINB5) for Simbrah cattle. Conclusion: Only 6,265% of the markers associated with growth traits were found using CWAS and GWAS. The associated markers using the CWAS analysis, which were not associated using the GWAS, represents information that due to the model and priors was not associated with the traits.

• Journal of Animal Science and Technology
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• 제65권6호
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• pp.1194-1204
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• 2023

Meat quality comprises a set of key traits such as pH, meat color, water-holding capacity, tenderness and marbling. These traits are complex because they are affected by multiple genetic and environmental factors. The aim of this study was to investigate the molecular genetic basis underlying nine meat quality-related traits in a Yorkshire pig population using a genome-wide association study (GWAS) and subsequent biological pathway analysis. In total, 45,926 single nucleotide polymorphism (SNP) markers from 543 pigs were selected for the GWAS after quality control. Data were analyzed using a genome-wide efficient mixed model association (GEMMA) method. This linear mixed model-based approach identified two quantitative trait loci (QTLs) for meat color (b^*) on chromosome 2 (SSC2) and one QTL for shear force on chromosome 8 (SSC8). These QTLs acted additively on the two phenotypes and explained 3.92%-4.57% of the phenotypic variance of the traits of interest. The genes encoding HAUS8 on SSC2 and an lncRNA on SSC8 were identified as positional candidate genes for these QTLs. The results of the biological pathway analysis revealed that positional candidate genes for meat color (b^*) were enriched in pathways related to muscle development, muscle growth, intramuscular adipocyte differentiation, and lipid accumulation in muscle, whereas positional candidate genes for shear force were overrepresented in pathways related to cell growth, cell differentiation, and fatty acids synthesis. Further verification of these identified SNPs and genes in other independent populations could provide valuable information for understanding the variations in pork quality-related traits.